Poor Things
Specimen ledger / L11N883+1

Layer 11 · Neuron 883 · boosted

L11N883+1

Word quirks:

“ingers”“改”“出现”“改革”“ Basis”“桌”“ense”“皇”

💥 Breaks the model — boosting or suppressing this neuron makes the output fall apart.

Identity (according to the specimen itself)

The reply didn't hold together

" s s s " s s s s � s s s s ss s s s s s s s s s ss �� s s

Nearest neighbors

Specimens with similar replies or word quirks. Similarity runs from −1 to 1; 1 is identical. These are leads, not shared mechanisms. How profiles are built.

By word quirks Profile recipe

SpecimenSimilarityWord quirks
1. L11N926-1💥0.93“改”“ingers”“马”
2. L11N4675+1💥0.88“ingers”“ Basis”“桌”
3. L11N1079+1💥0.86“ingers”“改”“示”
4. L11N3366-1💥0.81“"”“:"”“理想”
5. L11N2321+1💥0.81“ingers”“示”“roso”
6. L24N7990+1💤0.81“改革”“的改革”“冥”
7. L28N5232-1💤0.79“科”“行列”“呈”
8. L31N2526-1💥0.78“任”“集”“改”
9. L27N6253-1💤0.78“切”“尹”“改变”
10. L26N1723+1🕒0.78“染”“转”“江山”

Shadow specimen, apart from the ten: L11N883-1💤, -0.22.

Cousins · specimens sharing a neuron

No specimen with replies shares this neuron yet.

Technical details

Quick scan: measure prediction shifts on fixed reference text. Short test: generate replies to a small set of prompts. Longer test: extend to a larger set. Full test: run the full prompt suite. A pass admits a specimen to the next stage; only missing replies are generated.

Layer 11, neuron 883, dose +1. This specimen has no prompt-suite replies yet. Its quick-scan results, when available, appear below. Its quick-scan row (KL 10.84, top-1 agreement 0.00) is outside the band that feeds the short test (KL 1 to 2.5, agreement 0.5 to 0.65), so it stays at the quick scan unless someone queues it by hand. A hand pick goes straight to the full test. See Method for the tiers.

Quick scan · prediction measurements

Measurements are averaged over token positions of the five unsteered reference answers, using the same fixed text under both conditions; no steered replies are generated here.

  • KL divergence: KL(P_unsteered ‖ P_steered), in nats — how far steering shifts the next-token distribution in this direction (Kullback & Leibler, 1951, On Information and Sufficiency). Unsteered ≈ 0.001.
  • Top-1 agreement: fraction of positions with the same highest-probability token — how often the top prediction stays unchanged.
  • ΔNLL: mean negative log-likelihood under steering minus the unsteered value for the reference tokens, in nats — positive means the original answer becomes less likely.
  • Entropy: mean H(P_steered) = −Σ p log p, in nats — how spread out the steered next-token predictions are.

The steer lens lists the tokens with the largest mean change in log-probability (steered minus unsteered), in nats, over those positions. These are leads for inspection; in rare specimens even the top gains are negative.

SettingKL divergenceTop-1 agreementΔNLLEntropySteer lens
L11N883+1
t0-v0.1
10.8420.0011.2749.59 Top boosted tokens ↑
L11N883-1💤 shadow specimen
t0-v0.1
0.5780.700.7941.29 “ ***”“ **”“ ****”“ basically”“ **'”“**”“ **"”“ **“”

Method

A specimen is a fixed steering configuration of Qwen3.5-4B: one MLP neuron or a pair, each with a signed dose. Unsteered is the control. L identifies the layer; N, the neuron.

Additive activation steering. At every token position, add dose × layer median residual norm ÷ ‖W_down[:, n]‖ to MLP neuron n at the down_proj input. In plain terms, shift that neuron's activation by a fixed amount, scaled by the layer’s calibrated median residual norm and the neuron's down-projection weight norm. Positive doses push up; negative doses push down. Dose is normalized intervention size, not a percentage or probability.